Another Apple-to-switch-Macs-to-ARM post. "Apple engineers have grown confident that the chip designs used for its mobile devices will one day be powerful enough to run its desktops and laptops, said three people with knowledge of the work, who asked to remain anonymous because the plans are confidential. Apple began using Intel chips for Macs in 2005." No idea when Apple will make the switch, but they will do it. I'm thinking 5-10 year timeframe.

Yes, but if you have a very difficult calculation, would a single 500 Mhz CPU solve it slower than 10 500 Mhz ones? The 10 version can do the same calculation 10 times in the same amount of time as the single CPU, but can it do a single instance faster?

Yes, but if you have a very difficult calculation, would a single 500 Mhz CPU solve it slower than 10 500 Mhz ones? The 10 version can do the same calculation 10 times in the same amount of time as the single CPU, but can it do a single instance faster?

While there is no guaranteed improvement, I think it is imporant to keep in mind that multi-core systems can improve performance or throughput even if all they are running is single threaded processes.

Because they are almost certainly running multiple processes and being able to dedicate a core to a certain process leads to optimization options, e.g. never ever having to flush caches, potentially having dedicated memory or I/O lines, etc.

Multithreading improves the utilization of multipe-core CPUs, aber multithreading is only one of two widely deployed parallel-processing strategies (the other obviously being multiple processes)

More cores will allow each core to spend more time on a certain task, but they can't work together to do one task faster (I think).

So having a whole lot of ARM chips in your Mac doesn't make it faster at CPU intensive tasks than a Mac with 4 or 8 x86 based cores.

Then again, do they need to be? Are there so many tasks that require a lot of CPU to make it show?

When you move from a normal hard disk to solid state you'll notice what a bottleneck it was.

The CPU spends a lot of time being idle. So my guess would be that a computer with a solid state disk, enough and quicker memory, faster system bus can work very well even if it has ARM CPUs compared to a x86 machine.